[PATCH] autoconf: Add test for sys/select.h header file

[Jakub Narebski <jnareb@gmail.com>]

Some systems like HP-UX don't have sys/select.h; the select stuff
is already present in some other headef file (e.g. sys/time.h for
HP-UX).

Companion to
  "some systems don't have (and need) sys/select.h"

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
---
It could be alternately just squashed together with
"some systems don't have (and need) sys/select.h" by Robert Schiele.

Robert, could you please check this patch on HP-UX? It does work
correctly on Linux (which has sys/select.h).

 config.mak.in |    1 +
 configure.ac  |    6 ++++++
 2 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/config.mak.in b/config.mak.in
index 40b14d9..ee6c33d 100644
--- a/config.mak.in
+++ b/config.mak.in
@@ -30,6 +30,7 @@ NO_CURL=@NO_CURL@
 NO_EXPAT=@NO_EXPAT@
 NEEDS_LIBICONV=@NEEDS_LIBICONV@
 NEEDS_SOCKET=@NEEDS_SOCKET@
+NO_SYS_SELECT_H=@NO_SYS_SELECT_H@
 NO_D_INO_IN_DIRENT=@NO_D_INO_IN_DIRENT@
 NO_D_TYPE_IN_DIRENT=@NO_D_TYPE_IN_DIRENT@
 NO_SOCKADDR_STORAGE=@NO_SOCKADDR_STORAGE@
diff --git a/configure.ac b/configure.ac
index af177fd..85d7ef5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -235,6 +235,12 @@ test -n "$NEEDS_SOCKET" && LIBS="$LIBS -lsocket"
 ## Checks for header files.
 AC_MSG_NOTICE([CHECKS for header files])
 #
+# Define NO_SYS_SELECT_H if you don't have sys/select.h.
+AC_CHECK_HEADER([sys/select.h],
+[NO_SYS_SELECT_H=],
+[NO_SYS_SELECT_H=UnfortunatelyYes])
+AC_SUBST(NO_SYS_SELECT_H)
+#
 # Define OLD_ICONV if your library has an old iconv(), where the second
 # (input buffer pointer) parameter is declared with type (const char **).
 AC_DEFUN([OLDICONVTEST_SRC], [[
-- 
1.5.3.7